2008-06-22

The funny shape of the East China Sea "co-development" zone

The funny shape of the co-development zone in East China Sea recently nogotiated between China and Japan has puzzled many. I have speculated some reason in the choice of location (e.g. as far from Diaoyu / Senkaku as possible, largely on the disputed zone but includes a bit of the area west of Japan claim line to show goodwill, etc.) But the shape is still mysterious.

One theory (according Yomiuri - in its report also said explicitly now that Longjing Asunaro is not within the area) is that this area is chosen so that it satisfies two conditions1) as far north as possible (as I speculated)2) but avoid any potential dispute with Korea (!!!)

One may ask, what does Korea have anything to do with this. The map above shows (in white outline) the area stipulated by the February 1974 agreement between (South) Korea and Japan, as their codevelopment zone. Coordiantes of the polygon corners are:

Point 1 32°57.0'N 127°41.1'E

Point 2 32°53.4'N 127°36.3'E

Point 3 32°46.2'N 127°27.8'E

Point 4 32°33.6'N 127°13.1'E

Point 5 32°10.5'N 126°51.5'E

Point 6 30°46.2'N 125°55.5'E

Point 7 30°33.3'N 126°00.8'E

Point 8 30°18.2'N 126°05.5'E

Point 9 28°36.0'N 127°38.0'E

Point 10 29°19.0'N 128°00.0'E

Point 11 29°43.0'N 128°38.0'E

Point 12 30°19.0'N 129°09.0'E

Point 13 30°54.0'N 129°04.0'E

Point 14 31°13.0'N 128°50.0'E

Point 15 31°47.0'N 128°50.0'E

Point 16 31°47.0'N 128°14.0'E

Point 17 32°12.0'N 127°50.0'E

Point 18 32°27.0'N 127°56.0'E

Point 19 32°27.0'N 128°18.0'E

Point 20 32°57.0'N 128°18.0'E

Point 1 32°57.0'N 127°41.1'E

The problem is, in 1974, China was still a closed country, far behind the bamboo curtain. This area overlaps with the Chinese claimed line (based on the Ocean trough, and 200 nautical miles -- shown in the map above). To make real progress and not complicate the problem it thus makes sense to defer any discussion that may involve another new interest party (which is also highly nationalistic).

The Chinese Government holds that, according to the principlethat the continental shelf is the natural extension of the continent,it stands to reason that the question of how to divide the continentalshelf in the East China Sea should be decided by China and theother countries concerned through consultations. But now theJapanese Government and the South Korean authorities havemarked off a so-called . . . “joint development zone” . . . behindChina’s back. This is an infringement on China’s sovereignty"

p.s. It is a bit puzzling for me to understand why Japan had agreed to such a zone, as the south portion of the polygon extends far south of Cheju Island (or even Huang yan reef, which is the weaker version of 'okinotori' for Korea). It actually extended south of Kyushu and as far south as the latitude of Okinawa.

Note Yumiuri had a strange (and wrong) label of Sino-Korea median line。 (1) a China-Korea line would run North-South wise instead of East-West wise, (2) there is no median line agreed at between China and Korea. what is relevant is the 200 nautical line as indicated in the first map of this post. 日中の東シナ海ガス田協議で、翌檜(あすなろ)（中国名・龍井）を共同開発の対象としないことで合意していたことが２０日、分かった。 日中ともに単独開発も行わず、翌檜は事実上放棄される。翌檜は〈１〉中国と韓国の境界の基準となる「中間線」〈２〉日韓大陸棚共同開発区域――に近接しており、開発すれば韓国と摩擦を生じかねないと判断、韓国に配慮した。 日中交渉筋によると、両政府は翌檜の共同開発を一時検討。しかし、ガスを含む地層が、中韓の「中間線」をまたぎ日韓大陸棚共同開発区域に広がっている可能性があることがわかった。開発すれば、韓国が「資源を吸い取られる」と主張する懸念があった。一連の協議には韓国は加わっておらず、日中両政府は、翌檜の開発断念で一致した。 政府が１８日に正式発表した東シナ海ガス田開発に関する日中合意では、翌檜は共同開発の対象から外され、翌檜南側の海域が共同開発の対象となった。理由について、政府は「交渉の結果としか言えない」と説明していた。 東シナ海で日本が中国に共同開発を求めた４ガス田のうち、白樺（中国名・春暁）は日本が出資する形の共同開発で合意した。（2008年6月20日14時43分 読売新聞）